61-year-old Melody Carol Hinshaw was killed at about 11 p.m. Sunday when a vehicle ran into the back of her motorcycle on I-635 north between Metropolitan Avenue and Kansas Avenue. Hinshaw was thrown from the motorcycle after the impact. She was wearing a helmet, investigators said.

The driver of the teal Ford Focus that struck Hinshaw was not injured. Police said they believe he's about 25 years old and they're still hoping to find him.

Investigators said they want to know more about the circumstances leading up to the crash, including whether Hinshaw was driving slow or whether the Focus was going too fast.

"It looks simple, but we know it's probably not as simple as we are seeing right now," said Howard Dickinson of the Kansas Highway Patrol. "Another set of eyes and ears is going to help us tremendously."

Investigators said they have a start, but the public may be able to provide more information.

"It's one of those accidents, we are so used to CSI these days, we expect everything to be so cut-and-dry these days, we expect to get all the facts," said Dickinson. "In this case, we just want a little bit more."

Police are asking for any witnesses who might've seen the crash to call 913-782-8100 and ask for Master Trooper Candice Breshears or Trooper Jason Ruffin.